At present, a motor is usually used to drive a brushroll to roll via a drive belt in an upright vacuum cleaner, so as to clean a surface to be cleaned. When the drive belt is mounted, the drive belt needs to be in a loosened state. In a using process, however, the drive belt needs to be tensioned to realize transmission. In the upright vacuum cleaner in the related art, an independent tensioning device is adopted to tension the drive belt, but results in a complicated structure and inconvenient operations.